UPDATE 1-Gassi ruling will not affect Algerian ops -Repsol

* Repsol, Gas Natural say business as usual in Algeria

* No significant impact to either companies' earnings

* Sonatrach to buy Repsol, Gas Natural stakes in LNG project

* Sonatrach does not have to compensate for investments made

(Adds Repsol quote, background)

MADRID, Nov 27 (Reuters) - Spanish oil company Repsol (REP.MC) said a ruling on a dispute between it, its Gas Natural (GAS.MC) affiliate and Algerian state oil company Sonatrach over the Gassi Touil gas project would not affect Repsol's business in the country.

Repsol has exploration and production rights in five blocks in Algeria's southern desert and is producing oil and gas from two of them, according to the company's website.

The International Court of Arbitration has ordered Sonatrach to acquire its Spanish partners' stakes in their abandoned project to build a gas liquefaction plant in Algeria but not compensate them for investments they made, Repsol and Gas Natural said in separate statements.

"This dispute started in 2007 and its outcome will not affect the usual business of Repsol and Gas Natural in Algeria," the Spanish companies said.

Both companies said the ruling on the project will not have a significant impact on their earnings, with Repsol saying that it will write down assets related to the projects with an impact of about 105 million euros.

Repsol and Gas Natural announced in 2007 that Sonatrach had unilaterally terminated a joint venture to develop the Gassi Touil field and build a gas liquefaction plant to export the gas.

Sonatrach denied that it had decided to end the project, saying that it would seek substantial damages from the Spanish companies for failing to meet the terms of the agreement. (Reporting by Jonathan Gleave, Editing by David Cowell) ((jonathan.gleave@thomsonreuters.com; +34 91 585 2159; Reuters Messaging: jonathan.gleave.reuters.com@reuters.net))